New project TT Performance Puller gearbox/frame, set up for 8 wheelbase, 10.5 overall length. Made from 1 x 1 1/2 x 1/8w aluminum tubing, weighs around 5 ounces. The shaft spacing is 1 1/64 and 1 9/64 so you can install 9-56-9-64 gears for example. A decent buy at $50. May still be available assembled with gears, shafts, bushings, engine mount, and axles for $200 from Benson Machine Works.